The link to download Firefox from the Android Market will not work on phones with incompatible hardware. You can check if your phone is compatible here:

https://wiki.mozilla.org/Mobile/Platforms/Android

Even on some supported devices, a bug in the Market software prevents Firefox from showing up. This may be related to the fairly recent Android Market app update. If you go to Settings/Applications/Market and choose "Uninstall" you can uninstall the update, and then search for and install Firefox from the marketplace.

Or, if you have a supported phone, you can download the app directly from here:

http://ftp.mozilla.org/pub/mozilla.org/mobile/releases/4.0b3/android-r7/multi/

(Note: To download the app directly for an AT&T phone, you will have to search for instructions on "sideloading" the APK file, since AT&T disables the option to install from non-Market sources.)

I downloaded the app directly from the Mozilla site given in the second URL and it is working marvelously. The first approach recommended did not work. After uninstalling the Android Market app, any attempt to download Firefox mobile with a browser reinstalled the Market app which then blocked Firefox mobile from downloading.

Thanks a lot for your help.

Got the app through this link as well, installed the update, but my experience with it is nowhere near "Marvelous". Now i understand why Mozilla removed the x10 from the compatibility list. :(

I've tested a previous beta called Firefox, this one is called Fennec, don't know why the name change but both performed poorly, slow, random crashes, when in background it brings the entire phone to a crawl. My model is running Generic x10a firmware, 2.1 Android with JIT enabled.

disappointed.